Semiconductor device and method for fabricating the same

Abstract

A method for fabricating semiconductor device is disclosed. The method includes the steps of: providing a substrate having a first fin-shaped structure thereon; forming a spacer adjacent to the first fin-shaped structure; using the spacer as mask to remove part of the substrate for forming a second fin-shaped structure, in which the second fin-shaped structure comprises a top portion and a bottom portion; and forming a doped portion in the bottom portion of the second fin-shaped structure.

What is claimed is: 
     
       1. A semiconductor device, comprising:
 a substrate having a metal oxide semiconductor (MOS) region defined thereon and the MOS region comprises a first conductive type; 
 a fin-shaped structure having a top portion and a bottom portion on the substrate, wherein the top portion and the bottom portion comprise same material; and 
 a first doped region adjacent to one side of the fin-shaped structure in the bottom portion and a second doped region adjacent to another side of the fin-shaped structure in the bottom portion, wherein the first doped region and the second doped region comprise a second conductive type and an edge of the first doped region and an edge of the second doped region together constitute a V-shaped profile, and the first doped region and the second doped region both extend to and directly contact a slanted sidewall of the bottom portion of the fin-shaped structure. 
 
     
     
       2. The semiconductor device of  claim 1 , wherein the doped region comprises boron or phosphorus.